First pitch: Lo and Fields are the Astros’ two-person closers committee

The Astros’ closer-by-committee has officially become a two-person committee between righthanded rookies Josh Fields and Chia-Jen Lo.

“I’ll fluctuate between (Lo and Fields) based on the workload previously leading up to that game,” Astros manager Bo Porter said. “But it’s a good option to have both of those guys pitching well.”

Porter vowed to have a closer-by-committee after Jose Veras was traded to the Detroit Tigers on July 29. Lo, who was called up from Class AA Corpus Christi on July 30, earned his first major league save Tuesday night against Oakland. Fields, who picked up his first career save on Aug. 5 against the Red Sox, earned his second save on Wednesday night.

Lo was warming up in anticipation of another save situation on Friday night before Chris Carter hit a three-run homer and Matt Dominguez followed with another homer in the top of the ninth to go ahead 8-2 and end the save situation.

Lo has been plagued by injuries during his minor-league career, which is why he had only 70 appearances (five as a starter) since signing with the Astros in 2009. Because of Lo’s injury history, Porter hopes to use him whenever he warms up.

“That’s why he came in the game (Friday) night, because he was already hot,” Porter said. “In that situation, do you want to bring your closer once you get the three-run homer? No, but I made the decision (that) he’s hot (and) I’m not going to sit him back down. He’s coming in the game.”

Asked if his comments meant that Lo was his closer, Porter said, “last night he was.” He then acknowledged that Lo and Fields are his two closers.